Some Valuable Manpower Loading Data

Figure 3[2] shows typical manpower loadings for the design
and construction forces on the same sample of building projects as for Figure
2.

Several broad points are of interest here:

The manpower loading curve on a construction site over the duration of the
construction schedule is typically an asymmetrical bell curve

It is well represented by the trapezoid shown in the figure, where labor peaks
at about 160% of average, from the 50% to 75% points of the construction schedule

The man hours required for working drawings is approximately three times that
required for the concept/feasibility consulting work

Figure 3: Manpower Loading

Depending on the type of facility, the total man-hours invested by management
and its design teams will amount to at least 25% of the on-site labor man hours,
as shown in Figure 4[2].

Figure 4: Man Hours Invested by Management

Since on-site labor constitutes approximately 40% of the construction cost,
it follows in very general terms that one dollar invested in design effort corresponds
to ten dollars of construction investment

A "fast -tracking" approach will enable some overlapping of the working drawings
and early construction stages, perhaps as much as 30%. More than this will be
counter productive in terms of increased time and cost of coordination efforts